KR20060069994A - Apparatus for transferring a wafer - Google Patents

Abstract

In a wafer transfer apparatus for transferring semiconductor wafers between wafer processing apparatuses, horizontal arms extend horizontally, and wafer supports are disposed at both ends of the horizontal arms. The drive unit moves the horizontal arm in the extended direction while supporting the horizontal arm. A lifter installed in the drive unit raises the wafer supported on one of the supports, and lowers the raised wafer to be supported on the other of the supports. Accordingly, the supports are designed to exchange wafers by the lifter, thereby performing the same function as rotating the wafer without the driving unit for rotating the horizontal arm.

Description

Wafer Transfer Device {Apparatus for transferring a wafer}

1 is a perspective view illustrating a wafer transfer apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view illustrating the horizontal arm and the driving unit illustrated in FIG. 1.

3 to 6 are side views for explaining a step of moving the wafer of the horizontal arm shown in FIG.

FIG. 7 is a schematic diagram illustrating the operation of the wafer transfer apparatus shown in FIG. 1 between the spin coating apparatus, the prebaking apparatus, the exposure and developing apparatus, and the postbaking apparatus.

* Description of the symbols for the main parts of the drawings *

100: wafer transfer device 110: horizontal arm

112: first support portion 114: second support portion

116: moving block 120: first drive unit

130: plate 132: lifter

140: guide portion 142: first side wall portion

144: second side wall portion 146: side opening

150: second drive unit 160: guide rail                 

200: spin coating device 300: pre-baking device

400: exposure and developing apparatus 500: post-baking apparatus

The present invention relates to an apparatus for transferring wafers. More particularly, the invention relates to a wafer transfer device for transferring wafers between wafer processing devices.

In general, a semiconductor device includes a fabrication (FAB) process for forming an electrical circuit on a silicon wafer used as a semiconductor wafer, and an electrical die sorting (EDS) process for examining electrical characteristics of the semiconductor devices formed in the fab process. And a package assembly process for encapsulating and individualizing the semiconductor devices with an epoxy resin, respectively.

The fab process includes a deposition process for forming a film on a wafer, a chemical mechanical polishing process for planarizing the film, a photolithography process for forming a photoresist pattern on the film, and the photoresist pattern using the photoresist pattern. An etching process for forming the film into a pattern having electrical characteristics, an ion implantation process for implanting specific ions into a predetermined region of the wafer, a cleaning process for removing impurities on the wafer, and a process for forming the film or pattern Inspection process for inspecting the surface;                         

The photolithography process is a process of forming a pattern as a photoresist to define a portion to be etched or ion implanted and a portion to be protected. To this end, a process of spin coating a photoresist on a wafer, an exposure process of aligning the photoresist and a mask, selectively irradiating light through the mask, and a process of developing the photoresist are sequentially performed.

The baking process is essential in forming the photoresist pattern. In general, the baking process is performed using a baking apparatus that heats a wafer by laying down a wafer having a preliminary photoresist pattern formed on a baking plate provided in a chamber.

Specifically, the type of baking process includes a dehydration bake to prevent the adhesive force of the photoresist from decreasing due to moisture remaining on the wafer before spin-on coating the photoresist on the wafer. The photoresist film functions as an etch protective layer by reinforcing the adhesive force of the photoresist and removing the remaining solvent of the developer after the pre-bake process for converting the liquid photoresist into a solid film, and after the exposure and development processes. There is a post-bake process to do this.

What is important here is the time difference between the baking process and the other processes. For example, after the dehydration bake process, a photoresist spin coating process must be performed before the moisture is adsorbed onto the wafer again. Accordingly, it is common for the spin coating device and the baking device to be disposed adjacent to and facing each other in a clean room. In addition, a wafer transfer device is provided between the devices in order to transfer the wafer in a short time.

The wafer transfer apparatus moves on a guide rail installed between the apparatuses to transfer the wafer between adjacently disposed spin coating apparatus, exposure apparatus, developing apparatus and baking apparatuses, and accesses the wafer to the robot arm to access the apparatus. The wafer is withdrawn or withdrawn using. To this end, the wafer transfer apparatus should include three driving units for driving the robot arm in a horizontal direction, a vertical driving unit for elevating the robot arm, and a rotation driving unit for rotating the robot arm.

However, as described above, the wafer transfer device has a high probability of error because three motors driving three directions simultaneously operate. The error causes the operation rate to drop, which leads to a decrease in the productivity of the semiconductor device. Therefore, the development of a wafer transfer device with less error occurrence rate is required by reducing the number of drive motors.

Accordingly, an object of the present invention is to provide a wafer transfer apparatus having a simplified structure in order to minimize an error occurrence rate.

According to an aspect of the present invention, there is provided a wafer transfer apparatus, comprising: a horizontal arm extending in a horizontal direction, a pair of support portions disposed at both ends of the horizontal arm and supporting a wafer; A first drive unit for moving a horizontal arm in the extended direction; a wafer disposed on the first drive unit, the wafer being supported on one of the supports, being raised, wherein the raised wafer is the other of the supports; And a lifter for lowering to be supported on the support.

According to an embodiment of the present invention, the apparatus further includes a second driving unit for moving the horizontal arm in a vertical direction.

The apparatus may further include a guide part connected to each other at an upper end and a lower end to face each other and defining a space for moving the first driving unit in a vertical direction. The second driving unit is installed on one sidewall of the guide part.

The wafer transfer apparatus accesses an apparatus for applying photoresist and an apparatus for baking a wafer to exchange semiconductor wafers between the apparatuses.

In this way, since the support parts can exchange wafers by the lifter, they can perform the same function as rotating the wafer without rotating the horizontal arm.

In addition, since there is no rotation drive part, the preventive maintenance time is shortened and the error occurrence rate is reduced, thereby improving the productivity of the wafer processing apparatus.

Hereinafter, the wafer transfer apparatus of the present invention will be described in more detail with reference to the accompanying drawings.

1 is a perspective view showing a wafer transfer apparatus according to an embodiment of the present invention, Figure 2 is a plan view showing a horizontal arm and a drive unit shown in FIG.

Referring to FIGS. 1 and 2, a wafer transfer apparatus 100 according to an embodiment of the present invention will be described. The wafer transfer apparatus 100 includes a horizontal arm 110 for transferring a wafer. The horizontal arm 110 extends in a horizontal direction, and a pair of supports 112 and 114 for supporting a wafer are disposed at both ends of the horizontal arm 110. Recess regions are formed in the support parts 112 and 114 to allow the wafer to be safely seated. Alternatively, the support parts 112 and 114 may be formed in a tong shape, and an upper part of the support parts 112 and 114 may be provided with an adsorption part for adsorbing a wafer using vacuum pressure.

A lower end of the horizontal arm 110 is provided with a first drive unit 120 for moving the horizontal arm 110 in the horizontal direction and a plate 130 for supporting the first drive unit 120. The first drive unit 120 is a ball screw type drive unit including a drive motor. However, the first drive unit 120 of the present invention is not limited to the ball screw type.

In the central portion of the plate 130, the wafer supported on one of the supports 112 and 114 is vertically raised, and the raised wafer is lowered to be supported on the other of the supports 112 and 114. There is a lifter (132) for making. In one example, the lifter 132 is composed of four pin type members. Although not shown, the plate 130 may include a cylinder connected to the lifter 132 to drive the lifter 132 up and down.                     

The wafer transfer device 100 includes a first sidewall portion 142 and a second sidewall portion 144 which are connected to each other and opposed to each other at an upper end and a lower end, and move the first driving unit 120 in a vertical direction. It is provided with a guide portion 140 for defining a space for making. Inside the first side wall portion 142 of the guide portion 140 is a second driving unit 150 for raising and lowering the horizontal arm 110, the first driving unit 120 and the plate 130 integrally; It is connected to the plate 130. The second drive unit 150 is a ball screw type drive unit including a drive motor.

Here, side openings 146 are formed between the first and second sidewall parts 142 and 144 of the guide part 140, so that the horizontal arm 110 moves the side openings 146 in the horizontal direction (X). Direction) to pass freely. And the lower end of the guide portion 140 is provided with a guide rail 160 for horizontal movement. Therefore, the wafer transfer device 100 moves to wafer processing devices (not shown) disposed around the guide rail 160, and accesses the wafer processing devices by horizontally moving the horizontal arm 110. It is possible to exchange wafers.

Hereinafter, the process of transferring the wafer W from the first support part 112 to the second support part 114 by the lifter 132 while the horizontal arm 110 moves horizontally will be described in detail with reference to the accompanying drawings. Let's look at it.

3 to 6 are side views illustrating the steps of moving the wafer W in the horizontal arm 110 in chronological order.

3 and 4, a wafer W drawn from a wafer cassette or a wafer processing apparatus disposed adjacent to the horizontal arm 110 is supported on the first support 112 of the horizontal arm 110. It is. The horizontal arm 110 is connected to the first driving unit 120 by the moving block 116, the lifter 132 is located at the central portion of the plate 130 supporting the first driving unit 120. It is mounted perpendicular to the plate 130. The horizontal arm 110 is moved in the horizontal direction by the moving block 116 receives the driving force from the first drive unit 120 of the ball screw type. In this case, when the wafer W supported by the first support part 112 is positioned on the lifter 132, the movement of the horizontal arm 110 is stopped. Accordingly, the wafer W is stably supported and raised by four pin-shaped lifters 132.

Referring to FIG. 5, in the state where the wafer W is raised by the lifter 132, the first driving unit 120 moves the horizontal arm 110 to the right. The horizontal arm 110 stops at a point where the second support part 114 is located at the lower end of the wafer W that is raised. Here, the lifter 132 is lowered so that the wafer W may be seated on the second support part 114. In other words, the wafer W may be transferred from the first support 112 of the horizontal arm 110 onto the second support 114 by the lifter 132.

Referring to FIG. 6, the wafer seated on the second support part 114 is moved to the left by the first driving unit 120, so that the wafer W is disposed on the left side of the horizontal arm 110. Transferred to a processing apparatus or wafer cassette (not shown). On the contrary, the process of transferring the wafer supported on the second support 114 to the first support 112 is the reverse of the process described above with reference to FIGS. 3 to 6.                     

Hereinafter, a process of transferring a wafer between devices in which the wafer transfer device 100 performs a photoresist process according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 7 is a schematic diagram illustrating a wafer transfer apparatus operating between a spin coating apparatus, a prebaking apparatus, an exposure and developing apparatus, and a postbaking apparatus according to an embodiment of the present invention.

As described above, the photoresist spin coating process, the prebaking process, the exposure and development process, and the post bake process should be performed sequentially while minimizing the time difference between the processes. For this purpose, the devices may have the arrangement as shown.

Referring to FIG. 7, a cassette C on which a wafer W on which a photoresist spin coating process is completed is loaded is placed on the rod portion 210 of the spin coating apparatus 200. The horizontal arm 110 of the wafer transfer device 100 selects a wafer W to be prebaked while lifting in the guide unit 140, and the horizontal arm 110 expands and contracts the cassette C. ), The wafer W is taken out. The wafer W is transferred to the pre-baking apparatus 300 disposed to face the spin coating apparatus 200. The transmission may be performed only by the horizontal movement of the horizontal arm 110 without the guide unit 140 or the horizontal arm 110 rotating. Since a detailed delivery process is similar to the operation process described above with reference to FIGS. 3 to 6, a detailed description thereof will be omitted.

Subsequently, the wafer transfer device 100 withdraws the wafer W having the pre-baking process completed and then moves on the guide rail 160 to access the apparatus 400 for performing subsequent exposure and development processes. Pass W). When the exposure and development process is completed, the wafer W is received from the apparatus 400 performing the exposure and development process and transferred to the post bake apparatus 500 facing the wafer W.

As described above, in the wafer transfer apparatus according to the present invention, a pair of support portions are disposed at both ends of the horizontal arm. A wafer supported by one of the supports may be transferred to the other support by using a lifter for raising the wafer supported by the support. In addition, by mounting a drive unit for horizontally moving the horizontal arm freely through the side opening of the guide portion, it is possible to perform the same function as the horizontal arm rotates.

In short, it is expected that the error occurrence rate is reduced by removing the conventional rotary drive unit and operating only by horizontal and vertical drive, thereby improving the device operation rate and further increasing the productivity of the semiconductor device.

In the detailed description of the present invention described above with reference to the preferred embodiments of the present invention, those skilled in the art or those skilled in the art having ordinary skill in the art will be described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (5)

Horizontal arms extending in a horizontal direction; A pair of supports disposed at both ends of the horizontal arm and for supporting a wafer; A first drive unit for moving the horizontal arm in the extended direction; And A wafer transfer device including a lifter for raising a wafer supported on one of the supports and for lowering the raised wafer to be supported on the other of the supports; The wafer transport apparatus of claim 1, further comprising a second driving unit for moving the horizontal arm in a vertical direction; The wafer transport apparatus of claim 2, wherein the second driving unit further comprises a guide portion for guiding vertical movement, the pair of side walls being opposed to each other while being connected to each other at an upper end and a lower end. The wafer transfer apparatus of claim 3, wherein the second driving unit is installed on one sidewall of the guide unit. The wafer transfer apparatus of claim 1, wherein a semiconductor wafer is exchanged between an apparatus for applying photoresist on the wafer and an apparatus for baking the wafer.

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